arm64: Check if GMID_EL1.BS is the same on all CPUs

Browse source

The GMID_EL1.BS field determines the number of tags accessed by the
LDGM/STGM instructions (EL1 and up), used by the kernel for copying or
zeroing page tags.

Taint the kernel if GMID_EL1.BS differs between CPUs but only of
CONFIG_ARM64_MTE is enabled.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Suzuki K Poulose <Suzuki.Poulose@arm.com>
Link: https://lore.kernel.org/r/20210526193621.21559-3-catalin.marinas@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

...

This commit is contained in:

Catalin Marinas 2021-05-26 20:36:21 +01:00 • committed by Will Deacon

parent 7513cc8a1b

commit 21047e91a5

4 changed files with 32 additions and 0 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

1

arch/arm64/include/asm/cpu.h

View file

7

arch/arm64/include/asm/cpufeature.h

View file

21

arch/arm64/kernel/cpufeature.c

View file

3

arch/arm64/kernel/cpuinfo.c

View file